1. Field of the Invention
The present invention generally relates to a storage apparatus, in particular, to a flash storage chip and a flash array storage system.
2. Description of Related Art
Along with the advancement of semiconductor technology, the development of electronic products has been going towards high processing speed and multitasking. The processing speeds of logic processors such as a central processing unit (CPU) and memories in computer systems have been continuously improved as well.
However, besides being affected by the processing speeds of various logic processors and the memory, the performance of a computer system is also affected by the access speed of the storage device thereof (e.g. a hard disk). Because the access speed of a storage device is not likely to be considerably improved due to some technical obstacles, the access speed of the storage device cannot keep up with those of the CPU and the memory and accordingly the performance of the entire computer system cannot be effectively improved.
The data transmission rate of a computer system is mainly determined by the transmission speed of the bus. In order to improve the performance of a computer system, various interfaces with improved performance have been developed one after another, such as integrated device electronics (IDE) interface, peripheral component interconnect (PCI) interface, and PCI Express (PCIe) interface etc.
Additionally, a technique of redundant array of independent disks (RAID) has been provided to improve the access speed of the storage device in a computer system. According to the technique of RAID, a plurality of sub-storage devices is combined into a storage device. A data to be read from or written into a RAID is divided into a plurality of portions and then the various portions are read from or written into the sub-storage devices of the RAID simultaneously. Accordingly, RAID offers faster access speed. In addition, to avoid data loss when a particular physical hard disk is damaged, the concept of parity check is adopted by the RAID technique for restoring data when necessary.
However, the RAID technique described above has to use a plurality of hard disks therefore the volume of a RAID is very large and accordingly cannot be applied to a small computer system. Thereby, it is needed to develop a RAID system which can be applied to a small computer system.